Universal o.d. release tool

ABSTRACT

A tool for releasing a male fitting from a mating female connector coupled together by a retaining element includes an elongated H-shaped handle, a bifurcated body including complementary body halves resiliently carried by one end of the handle in a spaced-apart relationship which embraces an outer surface of the connector in a fixed orientation substantially overlying a radial opening therein which exposes the retaining element, and an abutment member which extends from one or both of the body halves operable to radially penetrate the opening to displace the retaining element from an engaged position to an O.D. release position. A second bifurcated body including a second set of complementary body halves is carried on the other end of the handle. Finger members carried by the second body axially engages the retaining element to effect I.D. release of the connector.

INTRODUCTION

The present invention relates to application specific hand toolsemployed to reconfigure mechanical assemblies and, more particularly, torelease tools employed to de-couple fittings from mating connectors.More particularly still, the present invention relates to tools adaptedfor releasing tubular male conduit fittings from mating femaleconnectors.

CROSS REFERENCE

The present invention is related to a copending U.S. application filedon even date herewith entitled "O.D. - I.D. Combination Release Tool",U.S. Ser. No. 807,533 now U.S. Pat. No. 5,187,851 having commoninventors and assignee of interest. Furthermore, the present inventionis related to U.S. Ser. No. 07/629,933 filed Dec. 19, 1990 now U.S. Pat.No. 5,084,954 and entitle "Quick Connector Universal Release Tool".

BACKGROUND OF THE INVENTION

Quick connectors have long been used to facilitate assembly ofmechanical devices without the use of special tooling. This isparticularly true in complex automotive systems wherein numerous fluidconduit interconnections are required. In the design of quick connectorsused in the industry today, it is sometimes desirable to incorporate aninaccessible retaining mechanism with the fitting. Since the retainer isnon-accessible, a tool is needed to open the retainer fingers and thusallow the male fitting to be removed from the female housing. Althoughtools adapted for release of quick connector type fittings are known,they suffer from a number infirmities and no design has yet receivedwidespread acceptance. Because quick connect fittings are used on arange of standard tube sizes (typically 1/4", 5/16" and 3/8" outsidediameter), prior approaches have been to provide a separate special toolfor each tube size. Additionally, design differences between quickconnect fittings of the same size from one manufacturer to another havenecessitated different tools or the application of a tool in veryprecise positional relationship with respect to the fitting to effectthe de-coupling. This has proved extremely inconvenient and such toolsare not widely used.

Secondly, release tools have frequently been difficult to manipulate dueto the small size of the fittings and the relatively high pull apartforces involved. Known tools have tended to be fragile and easilybroken, even with proper use, thereby further discouraging theiracceptance. A related shortcoming of known tools is in their requirementfor two hand operation which is particularly difficult in manyinstallations where access is limited.

In the design of quick connectors used in the industry today, it issometimes desirable to place the connector in such an orientation so asto make the open female end inaccessible. Since it is impossible tocreate an expanding force on the I.D. of the retainer fingers to releasethe male tube in such cases, a tool is need to collapse the retainingfingers inwardly and free the tube and retainer as a single unit. Acurrent approach in use make use of a forked structure that slides on agrooved portion of the quick connector to create the collapsing motionon the retainer fingers. This grooved track creates weak spots in thehousing material and adversely effects the overall connectorperformance. The design is also exclusive of such connector size anddesign and requires that the groove track be molded into the femalehousing. Therefore, it cannot be used with any currently manufacturedplastic quick connectors already in the field.

BRIEF DESCRIPTION OF THE INVENTION

The present invention overcomes many of the above described shortcomingsof prior art quick connector release tools by providing a single toolwith universal application, fitting the majority of standard tube sizesas well as both metal and plastic type quick connectors of most knownconfigurations. Furthermore, the present invention provides aninexpensive tool of robust design which can easily be held andmanipulated by one hand.

According to the present invention, a tool which is adapted forreleasing male fittings from mating female connectors coupled togetherby a retaining element includes an elongated handle and a bifurcatedbody including first and second complimentary body halves which areresiliently carried by the handle in a spaced-apart relationship which,in application, embrace an outer surface of the connector in a fixedorientation to substantially overlie radial openings formed therein toprovide external accessibility to the retaining element. Lastly, anabutment member extends from one or both of the body halves which, inapplication, penetrates the female connector opening(s) to displace theretaining element from an engaged position to a released position toeffect release of the fitting from the connector.

In the preferred embodiment of the invention, the bifurcated bodyincludes first and second complimentary body halves which areresiliently carried by the handle. Further, an abutment member extendsfrom each body half which cooperate, in application, to penetrate theirrespective openings to displace the retaining element towards itsrelease position. This arrangement has the advantage of providing simpleconstruction and one hand operation.

According to another aspect of the invention, the body halves defineflange surfaces which circumscribe the abutment members to limitpenetration of the abutment members within the openings. Thisarrangement provides a degree of self-gauging of the tool andnecessitates relatively little attention of the operator.

According to another aspect of the invention, the abutment members havecharacteristic peripheral profiles which are similar to and slightlysmaller than that of the openings whereby the abutment members andflange surfaces cooperate to guide the tool to a predeterminedorientation with respect to the female connector. This arrangementprovides the advantage of allowing use of the tool without closeobservation of the user, such as in close conditions typically found inan automobile environment.

According to yet another aspect of the invention, a locator nose isprovided which extends from the body halves away from the handle which,in application, is operative to initiate engagement with the femaleconnector and momentarily engage at least one of the openings to limitrelative axially movement therebetween. This arrangement provides theadvantage of rapidly pre-aligning the tool with the female connectorduring the engagement process.

According to still another aspect of the invention, the abutment membersdefine opposed abutment surface which are generally diverging when thetool is at an at-rest condition and which, in application, arere-positioned to a substantially parallel orientation when displacingthe retainer to its release position. This arrangement has the advantageof radially guiding the tool towards its engaged position with thefemale connector and thereafter to displace the retaining element fromits engaged position to its release position while maintaining linecontact therebetween and thereby minimize the chance of distortion orrotation of portions of the retaining element during the releaseprocess.

According to yet another aspect of the invention, the handle, body andabutment members are integrally formed from a homogeneous material suchas plastic. This arrangement has the advantage of providing extremelylow unit cost.

Still another aspect of the present invention, includes a generallyH-shaped handle including a base portion and generally parallelresilient arm portions extending therefrom and wherein the complementarybody halves are carried by corresponding free ends of the arm portions.This arrangement has the advantage of simple design and a handle whichinherently resiliently positions the body halves with respect to oneanother and permits their momentarily displacement, in application, asthe tool is mounted on the female connector.

According to still another aspect of the present invention, the handleis provided with a through passage for receiving a tether or othersuitable member to ensure against loss. This arrangement has theadvantage of providing a more robust design to the handle as well asallows the tool to be attached or supported from another device.

These and other features and advantages of this invention will becomeapparent upon reading the following specification, which along with thedrawings describes and discloses a preferred and alternative embodimentof the invention in detail.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1, is a perspective view of the preferred embodiment of theuniversal release tool according to the present invention;

FIG. 2, is a top plan view of an enlarged scale of the tool of FIG. 1;

FIG. 3, is a side plan view of the tool of FIG. 2;

FIG. 4, is across-sectional view taken on line IV--IV of FIG. 2;

FIG. 5, is a cross-sectional view taken on line V--V of FIG. 2;

FIG. 6, is a perspective view of the preferred embodiment of the presentinvention in use;

FIG. 7, is an exploded, perspective view of a typical plastic bodiedquick connector assembly with which the tool of the present invention isemployed;

FIG. 8, is a broken, partial section view of the present invention inapplication with the quick connector of FIG. 7, with the male fittingand female connector in the latched condition;

FIG. 9, represents the application of FIG. 8, with the tool havingdisplaced the retaining element of the fitting radially inwardly torelease the male fitting and retaining element from the femaleconnector;

FIG. 10, is a broken, partial section view of the present invention inan alternative application with the quick connector of FIG. 7, with themale fitting and female connector in the latched condition;

FIG. 11, represents the application of FIG. 10, with the tool havingdisplaced the retaining element of the fitting radially outwardly torelease the male fitting for removal from the retaining element andfemale connector;

FIG. 12, corresponds to a cross-sectional view taken on lines XIII--XIIIof FIG. 8, but with the release tool in its pre-positioning orientation;

FIG. 13, is a cross-sectional view taken on lines XIII--XIII of FIG. 8;

FIG. 14, is a cross-sectional view taken on lines XIV--XIV of FIG. 9;and

FIG. 15, is an alternative embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED AND ALTERNATIVE EMBODIMENTS

Referring to FIGS. 1 through 5, a universal quick connector O.D. releasetool, shown generally at 10, includes an elongated handle portion 12, afirst body portion 14 configured to effect outside diameter (O.D)release of conventional quick connect fittings, and a second bodyportion 16 configured to effect inner diameter (I.D.) release of suchfittings. Handle 12 is generally H-shaped, including a base 18 and fourgenerally parallel arms 20, 22, 24, and 26 extending therefrom. Base 18and arms 20, 22 or, alternatively, base 18 and arms 24, 26 are deemed toform generally U-shaped handle portions. The junctures of arms 20, 22,24, and 26 with base 18 each have a reduced section and comprises aresilient hinge 28, 30, 32, and 34, respectively. Arms 22 and 26 are inapproximate alignment as are arms 20 and 24. The free ends of arms 20,22 each support first body halves 36, 38, respectively comprising firstbody portion 14. Likewise, arms 24, 26 each support second body halves40, 42 respectively, comprising second body portion 16. Arms 20, 22, 24,and 26 are generally rectangular in cross-section and each define afinger grip 44, 46, 48, and 50, respectively, on an outer surfacethereof approximately midway therealong. Base 18 supports a generallyrectangular placque 52 bearing informational, advertising or otherindicia 53.

Each first body half 36, 38 supports an inwardly directed abutmentmember 54, 56 located centrally thereon and has a generally rectangularcharacteristic peripheral profile (see FIG. 4). The inside surface offirst body halves 36, 3 8 is partially cylindrical, having a constantradius which corresponds with the outer diameter of the mid-range femaleconnector to be employed with tool 10 as will be described in detailhereinbelow. The inner surfaces of body halves 36, 38 define generallycylindrical flange surfaces 58, 60 which operate to selectively embracethe outer circumferential surface of a female connector as will bedescribed in detail hereinbelow. The opposed, outer surfaces of firstbody halves 36, 38 form finger grips 63, 65, respectively. The innermostsurfaces of abutment members 54, 56 form abutment surfaces 62, 64 which,in the position illustrated in FIG. 2, at rest, are configured to beslightly diverging from one another and from the center line ofelongation of handle portion 12. Nose protrusions 66, 68 extendleftwardly from first body halves 36, 38 and converge slightly inwardly.Arms 20, 22 each form an outwardly directing dog leg 70, 72 at theirrespective points of transition into first body halves 36, 38. Supportribs 74, 76 reinforce dog leg 70, 72, respectively.

Each second body half 40, 42 supports a generally acurate finger member78, 80, respectively. Finger members 78, 80 are circumferentially spacedto define a constant diameter fitting receiving passageway 82 having anaxis which is angularly off-set from the line of elongation of handle 11to provide clearance from an associated coupling as will be described indetail hereinbelow. Finger member 78, 80 are relatively flexible andspaced from one another and are thus subject to limited radialdisplacement. As illustrated, passageway 82 corresponds with the nominaloutside diameter of an associated male fitting conduit of a certaindiameter. However, it is contemplated that multiple finger members 78,80 could be employed and passageway 82 tapered as described in U.S. Ser.No. 07/629,933 to render the I.D. portion of tool 10 universal as wellas the O.D. portion. Each finger member 78, 80 is coextensive with theother and, in a preferred embodiment of the invention, has acharacteristic radius which remains constant. The variants discussed inU.S. Ser. No. 07/629,933 could be adopted herein and, thus, theapplication is incorporated herein by reference.

As best viewed in FIG. 1, on the free ends of arms 24, 26, respectively,on the side thereof opposite lateral sides 84, 86 of the free ends ofarms 24, 26, respectively, form a pinch point for squeezing the freeends of arms 24, 26 together. Semicircular laterally extending fingertabs 88, 90 depend from the free ends of arms 24, 26, respectively, andserve as a pinch point for urging tool 10 along fitting receivingpassageway 82. Generally rectangular webs 92, 94 are formed at the pointof transition between arms 24, 26 and second body halves 40, 42,respectively to provide rigidity and to form finger grips 96, 98,respectively, on the top surfaces thereof. Alternating converging anddiverging surfaces or chamfers 100, 102 and 104, 106, are formed onsecond body halves 40, 42, respectively, to enhance engagement with anassociated quick connect fitting.

Tool 10 is ergonomically optimized to be held in a single human hand108. Although handle portion 12 cooperates with first and second bodyportions 14 and 16, respectively, to perform differing functions, tool10, is deemed to be a single tool in that arms 22 and 26 function as asingle lever as do arms 20 and 24. As viewed in FIG. 6, tool 10 is heldin hand 108 for use of second body portion 16 for I.D. release of anassociated fitting while first body portion 14 provides gripping/guidingsurfaces. In this configuration, tool 10 is retained by the user's indexfinger and thumb grasping finger grip 48 and 50, respectively, for theapplication of squeezing forces as indicated by arrows 110 and 112,respectively. Simultaneously, arms 22 and 20 as well as first bodyportion 14 are captured within the palm of hand 108 for stability andleverage. Specifically, the middle finger and the base of the thumb ofhand 108 bear respectively against grips 63 and 65, respectively asindicated by arrows 114 and 116, respectively, in a squeezing motion.When first body portions 36 and 38 are pressed together, they, alongwith arms 20, 22, 24 and 26 serve as a handle which via hinges 28, 30,32, and 34, tend to slightly separate second body halves 40 and 42 inanticipation of engaging the male fitting of an associated coupling aswell as to provide two spaced pressure points to facilitate manipulationof tool 10. Thus, by alternating application of forces at arrows 110 and112 and then 114 and 116, tool 10 can be operated somewhat in a scissorsfashion pivoting about base 18 subject to the resiliency of the materialitself as well as the flexibility of the hinge points 28, 30, 32, and 34and base 18. Tool 10 is construded symmetrically about the axis ofelongation of handle portion 12 to enhance utility whereby it can beheld in either hand and approach an associated fitting from anydirection.

When first body portion 14 is to be employed to effect O.D. release ofan associated coupling, tool 10 would be reversed from the positionillustrated in FIG. 6 in which the thumb and index finger of hand 108would abut finger grip 63 or 44 and 65 or 46, respectively and middlefinger and thumb base would contact finger grip 50 and 48 and/or secondbody portion 16, respectively.

Referring to FIG. 7, an exploded view of a typical quick connectcoupling assembly 118 for which the release tool 10 would be employed isillustrated. Assembly 118 includes a female connector body 120, a maletubular fitting 122 and a retainer 124. Female body 120 has generallytubular construction of injection molded plastic or other suitablematerial and includes an enlarged end 126 forming an opening 128 forreceiving an end 130 of male fitting 122 therein. Opposed radiallyextending passageways 132 and 134 provide external radial accessibilityto the interior of enlarged end 126. Passageways 132 and 134 aregenerally rectangular in shape and the leading edge thereof (as viewedin FIG. 7) forms an abutment surface 136, 138, respectively. Acircumferential flange 140 formed on male fitting 122 adjacent end 130provides a second abutment surface. Retainer 124 includes twopaddle-like axially extending retainer tabs 142, 144 which co-act withabutment surfaces 136 and 138 and flange 140 to effect coupling togetherof female body 120 and male fitting 122.

Referring to FIGS. 8, 9, and 12 through 14, a typical application oftool 10 to effect an O.D. release of coupling assembly 118 isillustrated. By way of example, O.D. release may be required when malefitting 122 is integrally formed with a large diameter disposable fuelfilter 146 which is close coupled to opening 128 of female connectorbody 120 preventing axial access thereto. As viewed in FIG. 8, retainer124 maintains female body 120 and male fitting 122 in an engagedcondition whereby retaining tabs 142, 144 define a leftwardly facingabutment surface 148, 150 engaging the right-hand most surface of flange140, as well as rightwardly facing abutment surfaces 152, 154 engagingabutment surfaces 136, 138 of female body 120, respectively, to preventrelative axial displacement between female body 120 and male fitting122.

Referring to FIG. 12, O.D. release is initiated by positioning tool 10generally normal to female body 120 adjacent its enlarged end 126 andprobing with nose protrusions 66, 68 to locate passageways 132, 134.Inasmuch as nose protrusions 66, 68 have substantially similar lateraldimensions as the axial width of passageways 132, 134, once located asillustrated in FIG. 12, nose protrusions 66, 68 will snap resilientlyinto their illustrated position to axially fix tool 10 with respect tofemale body 120. Thereafter, the application of rightward force asindicated by arrow 156 will transition tool 10 from the positionillustrated in FIG. 12 to the position illustrated in FIG. 13 whereinabutment members 54, 56 self-locate within passageways 132, 134. In sodoing, abutment members 54, 56 engage the edges of female body 120defining passageways 132, 134 to correct any slight shewing ormis-alignment of handle portion 12 with respect to female body 120. Whenpositioned as illustrated in FIG. 13, first body halves 36, 38 arespaced radially outwardly from the outer surface of female body 120 by adistance which is equal or slightly greater than the degree of radialpurchase of abutment surfaces 152, 154 upon abutment surfaces 135, 138.As illustrated in FIGS. 8 and 13, abutment surfaces 62, 64 establish aline contact with the radially outermost edge of retaining tabs 142, 144at the point wherein they transition into abutment surfaces 152, 154,respectively. Surfaces 62, 64 remain in a slightly outwardly convergingorientation with respect to an imaginery center line of tool 10.

To effect O.D. release, radially inwardly opposed forces are applied asindicated by arrows 160 and 162 against finger grips 63, 65 to displacefirst body halves 36, 38 to their illustrated positions in FIG. 14wherein flange surfaces 58, 60 abut the outer circumferential surface ofenlarged end 126 of female body 120 to limit radial penetration ofabutment members 54, 56 within passageways 132, 134 and to ensure themaintenance of precise positional orientation of tool 10 with respect tofemale body 120. As best illustrated in FIG. 9, displacement of bodyhalves 36, 38 to their illustrated release position rotationallydisplaces retaining tabs 142, 144 radially inwardly to disengageabutting surfaces 152, 154 from surfaces 136, 138. In transitioningbetween the positions illustrated in FIGS. 8 and 9, body halves 36, 38rotate slightly about their respective hinge points 28, 20, to effectapproximate parallel alignment of abutment surfaces 62, 64. Becauseretainer 124 is formed of inherently resilient material, once itsrelease is effected from female body 120, it will tend to moverightwardly as viewed in FIG. 9 to enhance its removal in assembly withmale fitting 122. After release of coupling assembly 118, body halves36, 38 will resiliently return to the position illustrated in FIG. 13for removal in a direction opposite to that suggested by arrow 156.

Referring to FIGS. 10 and 11, the application of tool 10 in itsalternative I.D. release function is illustrated. Again, beginning witha pre-assembled coupling 118, tool 10 is aligned whereby the line ofelongation to handle 12 is generally normal to the axis of conduit 122.Thereafter, a V-notch 164 (refer to FIG. 2) within second body portion16 defined by chamfers 102 and 106 in body halves 40, 42, respectively,is pressed against conduit 122 to momentarily spread the free ends ofarms 24, 26 to enable positioning of passageway 82 concentrically withconduit 122 wherein the resilient nature of the material forming arms24, 26 will cause them to snap back or reassume their illustratedgenerally parallel orientation. At this point, the radially innermostsurfaces of finger member 78, 80 closely abut and substantiallycircumscribe conduit 122.

Once positioned as illustrated in FIG. 10, tool 10 is displacedleftwardly as indicated by arrow 166 until the leading edge of fingermembers 78, 80 abut flange 140. In so doing, the outer circumferentialsurfaces of finger members 78, 80 ramp along the radially innermostsurfaces of retainer tabs 142, 144 sufficiently to enable axial removalof male fitting 122 as indicated by arrow 167 in FIG. 11. Uponde-coupling of coupling 188, retainer 124 will remain in assembly withfemale body 120.

Finger grips 44, 46, 48, 50, 63, 65, 96 and 98, as well as finger tabs88 and 90 constitute a tactile indicator system which provide the tooluser with non-visual cues as to the tool's orientation as well aspredetermined force application points as was described hereinabove. Thesystem ensures optimal use of the tool 10, 168, particularly to sightlimited application.

In addition to the foregoing functions, it is envisioned that releasetool 10 could be applied to release fittings which include an integralrelease collar as described in U.S. Ser. No. 07/629,933. A detaileddescription of that process will be deleted here for the sake ofbrevity.

Referring to FIG. 15, an alternative embodiment of a universal O.D. -I.D. quick connect release tool 168, including a handle portion 170forming a H-configuration including a base 172 and arms 174, 176, 178,and 180 depending therefrom, is illustrated. The central portion of base172 has an increased section defining a through passage 182 suitable forreceiving a tether such as a beaded chain 184 for securing tool 168 toanother object. Laterally extending finger tabs 186, 188 are provided tofunction as described hereinabove with relation to finger tabs 88, 90 ofFIGS. 1-4. Instructional indicia 190 is provided on a top surface of oneof both of tabs 186, 188 to aid its user.

It is to be understood that the invention has been described withreference to a specific embodiment and variations to provide thefeatures and advantages previously described in that such embodimentsare susceptible of modification as will be apparent to those skilled inthe art. For example, it is contemplated that arms 20 and 26 and,separately, arms 22 and 24 could be formed into two relatively rigidstructures which are pinned at a pivot point formed in at theirrespective base portions for sensors-like operation. Accordingly, theforegoing is not be to construed in a limiting sense.

What is claimed is:
 1. A tool adapted for releasing a male fitting froma mating female connector coupled together by a retaining elementdisposed within said female connector and externally accessible throughopposed radial openings within the female connector, said toolcomprising: a general U-shaped handle including a base portion andgenerally parallel resilient arm portions extending therefrom;abifurcated body including first and second complementary body halvescarried by corresponding free ends of said arm portions in aspaced-apart relationship operable, in application, to embrace an outergenerally cylindrical surface of said female connector in a fixed,predetermined orientation substantially overlying said openings, and anabutment member extending from each body half, said abutment memberscooperating, in application, to radially penetrate said opening apredetermined distance to displace said retaining element from anengaged position to a release position; said body halves definegenerally cylindrical flange surfaces circumscribing said abutmentmembers operative to limit penetration of said abutment members withinsaid openings.
 2. The tool of claim 1, wherein said abutment membershave characteristic peripheral profiles similar to that of saidopenings.
 3. The tool of claim 2, wherein said flange surfaces andabutment members are operable, in application, to interact with saidopenings and an outside surface of said female connector to guide saidtool to a predetermined orientation with respect to said femaleconnector.
 4. The tool of claim 1, wherein said handle, body andabutment members are integrally formed from a homogeneous material. 5.The tool of claim 4, wherein said material is plastic.
 6. The tool ofclaim 4, wherein said material is metal.
 7. The tool of claim 1, whereinsaid handle base portion defines a tether receiving through passage. 8.The tool of claim 1, wherein said flange surfaces are substantiallycylindrical and extend essentially normally to a line of elongation ofsaid handle.
 9. The tool of claim 1, wherein said body halves andabutment members are formed symmetrically.
 10. The tool of claim 1,further comprising resilient hinges formed near an intersection betweensaid base portion and each said arm portion.
 11. A tool adapted forreleasing a male fitting from a mating female connector coupled togetherby a retaining element disposed within said female connector andexternally accessible through opposed radial openings within the femaleconnector, said tool comprising: a generally U-shaped handle including abase portion and generally parallel resilient arm portions extendingtherefrom:a bifurcated body including first and second complementarybody halves carried by corresponding free ends of said arm portions in aspaced-apart relationship operable, in application, to embrace an outergenerally cylindrical surface of said female connector in a fixed,predetermined orientation substantially overlying said openings, anabutment member extending from each body half, said abutment memberscooperating, in application, to radially penetrate said opening apredetermined distance to displace said retaining element from anengaged position to a release position, and a locator nose extendingfrom at least one of said body halves away from said handle, said noseoperative, in application, to initiate engagement with said femaleconnector and momentarily engage at least one said radial opening tolimit relative axial movement therebetween.
 12. The tool of claim 11,wherein said nose has a characteristic lateral width substantially equalto a characteristic lateral dimension of said abutment members.
 13. Thetool of claim 12, wherein one said nose extends from each body half in agenerally inwardly converging direction.
 14. The tool of claim 1,further comprising opposed, outwardly directed grip surface formed onsaid body halves.
 15. The tool of claim 1, wherein said abutment membersdefine opposed abutment surfaces which are generally diverging in anat-rest condition and, in application, are generally parallel when saidretaining element is in said release position.